UPCC 27825 A Phase 3 Randomized, Double-blind, Placebo-controlled Study of Pasritamig (JNJ-78278343), a T-cell-redirecting Agent Targeting Human Kallikrein 2, + Best Supportive Care Versus Best Supportive Care for Metastatic Castration-resistant Prostate Cancer (KLK2-comPAS)

Investigating the Effectiveness of an Investigational Medication for Metastatic Castration-resistant Prostate Cancer

Enrolling By Invitation
18 years or above
Male
Phase 3
663 participants needed
1 Location

Brief description of study

The purpose of this study is to evaluate the overall survival (length of time from the start of study to date of death from any cause) for pasritamig (JNJ-78278343) in combination with best supportive care (BSC) as compared to placebo with BSC in participants with metastatic castration-resistant prostate cancer (mCRPC; a stage of cancer that has spread beyond the prostate gland and is no longer responding to hormone therapies).

Eligibility of study

You may be eligible for this study if you meet the following criteria:

  • Conditions: Metastatic Castration-resistant Prostate Neoplasms
  • Age: 18 years or above
  • Gender: Male

Inclusion Criteria

  • Histologically confirmed adenocarcinoma of the prostate
  • Metastatic castration-resistant prostate cancer (mCRPC): Disease that is metastatic either to bone, any lymph node, or both without clear evidence of other metastatic sites at the time of screening by conventional imaging with computed tomography (CT) or magnetic resonance imaging (MRI) (chest, abdomen, and pelvis) and 99m^Tc bone scan
  • PSA greater than or equal to (>=) 2 nanogram per milliliter (ng/mL) at screening
  • In the opinion of the investigator, the next best treatment option is a clinical trial
  • Participants should have had all life-prolonging therapies for which they are clinically eligible in the opinion of the investigator and to which they have access. Prior therapies could have been given in any disease setting (not limited to mCRPC). In particular, prior treatment specifications include receipt of the following

Androgen-receptor pathway inhibitor (ARPI): Must have progressed on at least 1 ARPI and unlikely to benefit from retreatment with another ARPI

Taxanes: Should have received at least 2 previous taxane-based regimens. If a participant has received only 1 taxane regimen, the participant is eligible if:

  1. Cabazitaxel is not available
  2. The participant's physician deems the participant unsuitable to receive a second taxane regimen due to toxicity risk or prior intolerance Note: a taxane-based regimen consists of at least 2 cycles of a taxane (either as a single agent or in combination with other therapies) administered within the same 2-month period. Participants who cannot continue taxane therapy because of a documented Grade>=3 taxane related IRR are eligible for enrollment, even if they received fewer than 2 prior cycles of taxane treatment

Radioligand therapy: Should have been previously treated with at least 1 dose of Prostate-specific membrane antigen (PSMA)-targeted lutetium radioligand therapy (eg, lutetium Lu-177 vipivotide tetraxetan), unless one of the following applies:

  1. PSMA-targeted lutetium radioligand therapy is unavailable, not accessible, or not clinically indicated.
  2. The participant's physician deems the participant unsuitable to receive PSMA-targeted lutetium radioligand therapy.

Polyadenosine diphosphate-ribose polymerase inhibitors (PARPi): Should have been previously treated with PARPi, if the participant has a known germline or somatic BRCA mutation and treatment is available

  • Prior orchiectomy or medical castration (receiving ongoing ADT with a GnRH analog [agonist or antagonist]) prior to the first dose of study treatment and must continue this therapy throughout the treatment phase
  • Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
  • Participants are eligible if they have the following values:
    1. eGFR >= 30 milliliters per minute (mL/min) B) Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST) less than or equal to (<=) 5 times the Upper Limit of Normal (ULN) C) Serum total bilirubin <= 3 times ULN D) Absolute neutrophil count (ANC) >= 1.0x10^9/per liter (L) E) Hemoglobin >= 8.0 grams per deciliter (g/dL) F) Platelet count >= 75x10^9/L

Exclusion Criteria

  • Venous thromboembolic events within 1 month prior to the first dose of study treatment; uncomplicated (Grade <= 2) deep vein thrombosis is not exclusionary
  • Active autoimmune disease within the past 12 months that requires systemic immunosuppressive medications (eg, chronic corticosteroid, methotrexate, or tacrolimus)
  • Participants with Grade 1 or higher fever (>=38ºC) or active infection requiring systemic treatment within 7 days prior to randomization are ineligible. Participants must be afebrile (<38ºC) at the time of study treatment dosing unless approved by medical monitor
  • Clinically significant pulmonary compromise, particularly a requirement for supplemental oxygen use (>2 liters per minute (L/min) by nasal cannula) to maintain adequate oxygenation
  • Prior or concurrent second malignancy (other than the disease under study) for which natural history or treatment could likely interfere with any study endpoints of safety or the efficacy of the study treatment(s)
  • Any of the following within 6 months prior to first dose of study treatment:
    1. Myocardial infarction B) Severe or unstable angina C) Clinically significant ventricular arrhythmias D) Congestive heart failure (New York Heart Association class II to IV) E) Transient ischemic attack F) Cerebrovascular accident
      • Prior treatment with any CD3-directed therapy

This study investigates the effectiveness of an investigational medication in combination with best supportive care for patients with metastatic castration-resistant prostate cancer (mCRPC). The study aims to compare the overall survival of participants receiving the investigational medication with those receiving a placebo, both alongside best supportive care.

Participants in the study will be randomly assigned to receive either the investigational medication or a placebo, in addition to best supportive care. The study is double-blind, meaning neither the participants nor the researchers will know who is receiving the investigational medication or placebo. Regular assessments will be conducted to monitor the participants' health and response to the treatment.

  • Who can participate: Men with histologically confirmed adenocarcinoma of the prostate and metastatic castration-resistant prostate cancer are eligible. Participants must have a PSA level of at least 2 ng/mL and have progressed on at least one androgen-receptor pathway inhibitor. They should have received prior taxane-based regimens and radioligand therapy if applicable.
  • Study details: Participants will receive either the investigational medication or a placebo, both with best supportive care. The placebo is an inactive substance that looks like the investigational medication but does not contain any medicine.
Updated on 06 Jul 2026. Study ID: 25-1561
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